Automatic pin spotter control mechanism



April 18, 1961 M. SANDERS ETAL 2,980,424

AUTOMATIC PIN SPOTTER CONTROL MEOHANISM Filed April 4, 1957 7 Sheets-Sheet 1 OO .Og Y

April 18, 1961 lM. SANDERS I-:TAL

AUTOMATIC PIN SPOTTER CONTROL II/IEcHANIsI/I 7 Sheets-Sheet 2 Filed April 4, 195? April 18, 1961 M. SANDERS ETAL AUTOMATIC PIN SPOTTER CONTROL MEOHANTSM 7 Sheets-Sheet 3 Filed April 4, 1957 AIO April 18, 1961 M. SANDERS ETAL AUTOMATIC PIN SPOTTER CONTROL MECHANTSM 7 Sheets-Sheet 4 Filed April 4, 1957 A Trae/VEA( April 18, 1961 M. SANDERS ETAL 2,980,424

AUTOMATIC PIN SPOTTER CONTROL MEOHANTSM Filed April 4, 1957 7 Sheets-Sheet 5 .g R 2 my. ws w 4 M H III EN@ gm@ Aprll 18, 1961 M. SANDERS ETAL AUTOMATIC PIN SPOTTER CONTROL MECHANISM 7 Sheets-Sheetl 6 Filed April 4, 1957 III' NN @E INVENTOR. #0M/@ April 18, 1961 M. SANDERS ETAL 2,980,424

AUTOMATIC PIN SPOTTER CONTROL MECHANISM Filed April 4, 1957 7 Sheets-Sheet 7 ha I4,

552/ aff" 1404 "255 CHAA/A/EL S ffl' 4'; l

United States Pater AUTOMATIC PIN srorrnn CONT-nor MEcHaNisM Milton Sanders and Howard S. Halpern, Stamford, Conn., assignorsto American Machine .& Foundry Company, a corporation of New Jersey Filed Apr. 4, 1957, ser. No. 650,634

`s6 Claims. (11273-43) This invention relates to bowling pin setting machines and more particularly to lcompletely automatic bowling pin setting machines in which the `operations are e'lectrically controlled in accordance with conditions arising in the course of playing of -the' bowling games. More particularly the invention relates to Van `automatic control of a Vtime delay of a pinspotter by detecting pins in motion thus shortening the average -pinspotter cycle by having time delays of the pinspotter variable Vrather than fixed at the maximum expected duration oi' pin mot-ion, which is the .case in the presently Iused p'inspotters. The invention also :includes control vsystems for preventing the normal cyclic operation of the pin-setting machine when the iirst ball is a -gutter -ball and also when the first and the second balls in a frame are both `gutter balls. The invention also discloses a -control system which prevents the normal, cyclic operation of the machine, and more particularly, the prevention of the operation of its .pin-setting and resetting mechanism, when only pin #7 or pin #l0 is knocked ol lthe pin deck of the alley only by the irst ball without knocking down any other pins, and allowing the normal operation of the machine if either pin #7 or #1.0 is knocked ou-t by the second ball in any given Vframe. Knocking down of either pin #7 or pin #l0 by the second ball, withoutknocking down any additional pins, can take place only when the iirst ball is a gutter ball which leaves all pins standing for the second ball, and rolling of the ,second then knocks out only pin #7 or #10. Under such conditions playing of `the trame has been completed and, therefore, the disclosed system permits the normal operation of the pin-setting mechanism. vin bowling pin setting machines, one of the main problems is to make all operations as quickly as possible, and to make these operations comply with the rules of the American Bowl ing Congress. Someautomatic bowling machines now in use have a standard delay'time for operating pin setting machines to prevent the operation of the machine while any of the pins are iin motion. Thisl delay time, as a rule, is equal to the maximum pin motion time that may be encountered in any play. However, there is a much larger number of plays which do not produce any pin motion, such as' pin wobble, and, therefore, the maximum delay timerbuilt into the present machines is wasteful of time. This maximum delay time, as a rule, is derived from the maximum duration of a vpin wobble that can take place without producing apin fall. The

pinwobble may be defined as an oscillation of a bowll ing pin around its vertical axis'.` This oscillation maylne-compared with an oscillation of aupenduflumr, except that while inthe pendulum the center of' gravity is below the point of pendulum suspension, in the pin wobble, the center .of gravity of the pin is above the point of suspension which,in` this case, is the alley door sup porting the pin. The pin wobble, as a rule, therefore, is in a single vertical plane with the pin-iirst dedectng to one side and then to the other from its normal vertical position. The energy involved in pin wobble cannot exposition of `stable equilibrium which is reached when the center 4of gravity of the pin is -directly above the point ofcontact of `the-pin -with the alley door. lf more energy is supplied to the pin than that required to tilt it to its condition of lunstable equilibrium, the pin will fall over directly and not wobble. As the pin base becomes worn with use, the base edge becomes more rounded and the point of contact of the pin with the alley floor comes closer to the Vaxis of symmetry-of the pin. The position of unstable equilibrium is reached with a smaller tilt with the old pins, having -worn out bases, than with the new pins. For a new pin, the maximum duration of pin wobble is about vnine seconds and the maximum peak-to-.peak motion of the pin head is about ve inches. The fixed delay built into the 4pinspotters is less than line seconds because it is. unnecessary to hold up the operation ofthe machine all full nine seconds even if the maximum possible amplitude wobble does occur. It the pin does not fall within the iirst maximum amplitude, it, obviously, -Will not -fall as the vamplitudes diminish. However, the operation -of the `machine cannot be started until -the amplitude has died down sutliciently so as to produce proper engagementof the pin and the pin-sensing and respotting cups and avoid knocking down lof the wobbling pin by premature lowering of the respotting cup. Moreover, the players do not wish to see'the pinspotter go into operation until all wobble ceases, and the latter considerat'ion, which is of purely psychological nature, Vrequires the fxed time delay to be much longer than that required by thepin wobble itself. Usually this tixed time delay is of the order of 6 to 7 seconds. Since by far the larger number of plays do not produce any pin wobble, the operation of the pinspotter-can be expedited considerably by making the time delay equal to zero when there is no wobble and variable when there is wobble, the actual duration of any'speciiic delay being controlled by the wobble itself "so that the Vdelay is very short when thereis only a slight wobble and longer when the wobble is more pronounced.

There are also present, at times, such pin motions Vas pin spin and pin roll. The path of the rolling pin is approximately an arc of a circle and the pin spin usually is transformed into a pin roll after the spinning pin loses some of its energy. The duration of pin roll is limited by the dimensions of the alleyiloor and A,the presence of other pins. The pin roll and pin spin 'cease in less time than that required for pin wobble to cease. There'- fore, the duration of pin wobble rather than vthat of pin roll or pin spin, determines the maximum 'delay vneces-y sary in pinspotter operation. Y

in order to vincrease the intelligence of the detecting system still further it is also necessary for such detection system to provide a pin presence signal in addition to the pin wobble signal.` With the pin wobble and presence signal made available by the detecting system, the following improvements in the operating cycle of the pin# spotter become possible:

(l) Variable time delay 'for puttingpinspotter into operation, this time delay being controlled directly by pin wobble so that this time delay is made equal-to zero when there is no pin wobble.

V(2) Elimination of sweep and table operation when only pin #7 or pin #lis knocked out into pitbytlleA first ball.

(3) Elimination of sweep and tableoperation when` pinfall signal means by the momentjthefpin VislniockedY down. Y'

lows: one of the'simplest systems is the system based parent and non-transparentpatterns) are so arranged that the transmitted illumination is a function of pin position with respect to, the respective mask with a uniform lighteld illuminating the pins.l The light transmitted through the mask is focused on a photo cell whose output will havea varying component corresponding to pinwobble. If only one photocell is used for all ten pins, i.e., all ten pin images are focused on asingle photocathode, 'they resulting system will produce la X wobble-andpresence detector whichV will not indicate the Vpresence, or absence ofYV any individual pins. lIndividual pins lwnbble presence is obtained byiusing a 'usepara'te-pi -holelens and ajseparate photocell to examine the image of each'pin." 'Y' TheV additional ,versions of the,V systems 'all' utilize `an l' electro-magnetic phenomena for` producing an electrical .signalin response'to-a wobble and presence. v VariationsY the eIcono-magneticV or-electro'static Vlields unbalance Y electrical ncircuits Vto vvpro'ducefa modulated alternating current'wave corresponding Yto wobble andV a variable amplitudefsignal, Ora'change'in the level of the'signal to indicate pin presence.

stressed atthis point that ,whatever the detecting system is, it must be capable'of producing twoj typesbf signals,one for indicating wobble,1 and 'the t lother'and d iierent type of signal-for indicating presence.v Thesetwo types-of signals"Y are iirst produced Vina commontransducerandthey are then's'eparated'from'each Vother and directed totwo separate control' channels; The

"wobble signals Vcontrol,the"operation of the wobble sig# nal channel, and the'l presence signals icontrol'pthe opera-A Y Qtienof Ythe presence signal channel; InV the purelyieleclf 1?' trical detection j systerns, l theA transducer produces amodulated alternatingicurrent wave inresponse to ,vi/,ob-`

When the transducer is an optical transducer, two types of signals, AM. and LM. are also produced but the carrier wave is a direct currentcarrier as differentiated from the alternating current carrier. Since direct current ampliers are less stable than alternating current ampliiers, the A.M. and L.M.y signalsY in the above type of system may be transformed in the Aelectronic detection channels intoA.M. and LLM. signals having an alternating current carrier for eliminating theuse of direct current amplifiers.V L i f Itis therefore, an'object of this invention to provide Ypin wobble and pin presence detection systems.

.lt is anr additionalobject of this invention to provide purely electrical pin wobble and pin presence detection systems. v Y Y v Still another object of this invention is to provide an optico-electrical Vpin wobble fand pin presence detection system.

n An additional object vof this-invention is to provide transducersconvertinglthe' pin-` wobble, andthe pin 'p presence-and-absence intolY twoY corresponding "types of These signals, in turn, are -used Yin the same manner as` the signals from the photou cathodes,'wfor producing theV desired effects, in the relay Y systernused for initiating? thejoperatingcycle *of the pinspotter.V Y

ltfshould be signals produced on theY output sideoftheitranSducerS.

i Still-:another kobject'of -thisr invention is to provide a transducerfor converting thepin wobble-directly into an amplitude-modulated'electrical signal and the pin absence-,and-presence.directly into a level-.modulated electrical signal inthe same transducer. n v

Yet another objectV of Vthis invention is to provide an optical transducer in which thepin wobble isY converted into amplitude-modulated light signal; and the pin absenceand-presenceis converted vinto* a Vlevel-modulated'light signal. Y,

It is alsoan objectoi this invention tQProvide a relay system `actuated'by the transducers-ofthe above type, Ythe relay system in turn controlling thepperation of a pin-setting`machine in accordance with-.the Ygreater intel- ,i Vligence provided by the transducers and therelay system A -fwhichfis constantly responsiveito-the wobble and pres- Y rence .of the bowling-pins ,throughout the bowling game. 40'

' `It, is an additional Vobject of thisinvention to provide an .improved electrically controllediautoniaticlv bowling pin setting machine havingA a 'control system capable of responding to ,and ,controlling/,the time of operation of ble',rand a change in theilevel, oramplitude,'-of the-same alternatingcurrent waveiinY response to thevv absence of'A 1 V,a `prr 1 1.j -lnorderfto haveafclea'r'er understandingof the f termsmodulated wave and Ychange-1in leve fit-may Vbe Vhelpful to'say thatthejmodulatediwave signal is'pro- Y Vduced byusing apin wobble as al means for modulating .i Y agnormally constantV amplitudeY alternating fcurrent produced .by some i suit-ableV 'sourc'e,l such ias-a1; crystal- 5^ controlled oscillator:V The degreeiof :modulation-,is a

i i function of thefamplitude of thevvobble;V the larger eis theV wobble, thelarger is the modulation.V ".Thevv presence of a pin, .on the otherfhand, produces aconstant amplitude signalhaving ,'a 'constant amplitude a whenv` thev pin Vis VVpresent, and`; av constant" amplitude bV when vthepinY is vrY.absent?with Va being greaterv ornsmallerfthan bi K The' Y wobble signal, produced by the Vaboveclass `of systems, shallbelcalled as fthe amplitude.modulatedrsignalj orV Y the-A M, signalV to' correspondto the well-known, and' Y 1r;identicaluamplitude modulation'ujsed in radio, vtelevisin f 4andi'other'.forms rJfA;l\l.g communication'isystems, ask l dierentiated V,from 1,1`.'M.,y or-rfr'equencymodulation fsysteinsf. {The prie/:sence` signal `VsfhallbeA called fthe level' 4`j i, Y l .570

vln-the Vanpve termf-the wordY.nrodulationiV means the changelinthe levels'of vthesignal V,v/ hichi takes place; when the jpin sjrern'ovedffrein-itis'V normal kstanding lposition, Le.,-

knocked;down..l V5fifhisii'chan'ge.,inlevel takes piace at l followin'gdescription taken in connection j, 'panyingl drawings themachne when-there is arwobble offany pinor, alter:`

natively, preventing Vits operation when only pin #7 or pinitl() is-kn'ockedrdown byV thejiirst'ball 'when all pins Y are vpresent aftcrh'alljnbl `or ball-"#2 are jrolle'diwithout any Pins, ',ivvhtlifrareV known as l ffgutter Y, knocking Jover balls. i. K It is a furtherliobjectvof'this invention to provide an improved control system vr for L an automatic bowling pin setting machine, the control',V system having electrically 'Ycontrolledlmeans-responsive tobthe presence,Mv absence and wobblefofgpinsiafter.an impact 'ofaball' ontheb'owling pins, and having arelay'system-capable; oftimingthe VoperationV o f f the machine in 'response tojthe pin-wobble and pin 'presence signalskY Yet Vanother:objectof this invention is to* provide a Ypinspotterhavinga wobblefand-'presence detector provided withfapin presence VsystemV capableof; Yfurnishing a. visualV [display indicating the, Vpins Vleft` standing after VVthe-first orfthe'second,ballslare rolled inftheV course ofY ,if aframej'andto*indicatestrikes andspares., v

} @The novel features which` are .b lievedito be characteristicof the invention,`botly'as-.to'-itsforganization and ,method-ofgoper'ation, together withrfurthergobjects and advantagesflthereof, will be fbetter j uncleristorodv Vfrom. the

inventionY 'are illustrated -as exalrriples. o'f 'thel invention. Zlt is to be expresslyunderstood,howeverfthat thedraw- Vi ofthe invention. vRerlerring tofthe drawings:

'-detectionj system; i n t,

L.: fFigure'fl isv aiblckgdiesramoi fawlzble and presse@ f 1 Figure 2 is a block diagram of an optical wobble-and presence detection system;`

Figure 3 is a front elevational view of the camera used in connection with the system illustrated lin Fig. 2;

Figure 4 is a plan view of the viewing mask for the camera illustrated in Figs. 2 and 3.

Figure 5 is a schematic diagram of the electronic channel of Fig. 2;

Figure 6 is' a 'block diagram of an inductance pin wobble and pin presence detector system;

Figure 7 is the modified version of the inductance pin wobble and pin presence detector system disclosed in Fig. 6;

Figure 8 is a schematic diagram of the isolating detector used in the detection system disclosed in Fig. 7;

Figure 9 is a block diagram of a detection system using a bridge circuit;

Figure l0' is partly a schematic diagram and partly a block diagram of the detection system using an inductance bridge; t

Figure l1 is aside view of apin and dow coil used in conjunction with Fig. 10;

Figure l2 is partly a schematic diagram and partly a block diagram of the detection system using a capacitance bridge;

Figure 13 is a side view `of a pin and capacitor mounted .Qn the neer need .in eeninnetien with ,Fig-'1.2;

Figure l4. is a schematic diagram of the relay system Operated by the detecting systems;

' Figures 15 and 16 illustrate a suitable type `of gutter bell deteetingmeehenisrn Basic .components of ythe detection system Referring to Fig. l, it discloses a simplified Vblock diagram of a pin wobble and presence system for a single pin e2. When reilected light is used for detecting the wobble and presence o f the pin, the pin needs no modiiications of any kind. The light reflected by the pin produces the amplitude modulated light signal when the pin wobbles, and it produces the level modulated light signal when the pin is absent. These light signals are converted into the corresponding electrical signals by the detection system 3. The amplitude modulatedsignais (A .M.) are then separated from the level modulation presence signalsin the detection system 12 and are impressed on condenser 4 While the level modulation signals are impressed on a conductor 5. These two signals are then used to control the operation of a pinsetter in the manner pointedr out in the introductory part of the specification.

` When the detection system 3 is all electrical, o r electronic, system, a standard pin, without any additional modifications within Vthe pin'4 itself, may be used when a capacitive coupling between the base of the p in and a capacitor mounted in the alley tloor is used for converting pin -wobble and pin presence directly 'into the A;M, and LM. electrical signals. WhenV the capacitive effect is replaced -with the inductive effect, it is 'preferable to mount a small coil at the base of the vbowling pins for increasing the Auseful magnitude of wobble and presence signals. The bowling pins of the vabove type are .described morein detail in the copending 'U. S. application for patent of Milton Sanders having a Serial 'Number 615,736, filed on yOctober 11, 1956, and entitled Bowling Pin.

The Aabove detection systems are described mote in detail, below, beginning with the deerptien .ef the .Opticoelectronic system. Y

ptico-electronic detection is'ys'lenz` the detee'ting fend signal-Separating circuits is Shown in Fig- 5- Aeeerdngly; this. eystenn, be' gelserbed .6 connection twith Figs. 2 through 5. The transducer, per s e, which transforms mechanical movement of the pins, such as wobble and presence-absence, includes asource of light 30, pins A12, a pin-hole camera 10, and a mask 2 4 mounted Within the camera.V This optical transducer converts the. pin wobble into an amplitudemodulated light signal and pin presence into alevel modulated'light signal. These light signals are focused on .the photocathode 52 of a photo-cathode multiplier 50, Fig. i5, where the light signals are converted into electrical signals and the electrical signals are then used for controlling the operation of the pinspotter machine. Figs. l through 5 illustrate only.one optico-electrical detection channel for one pin; the overall system includes ten identical individual channels of the above type, one chanel for each pin. Each channel furnishes information concerning the status of its pin in terms of wobble ,and presence and these signals are 4.used for controlling the operation of the pinspotter. Only one wobble-and-presence channel is illustrated for simplifying -the desciiption and drawings.

Referring to Figure 2, it illustrates the relative 'position of camera 1 0 with respect to'the alley floor 11 and pins 12. 'The most advantageous location for camera 10 is on an alley mask 13 directly behind the pinfa'll signal means 14. Camera 10 for pin #l is "in a Yenial plane passing through the central, longitudinal (axis o f the alley, and the remaining cameras are pcsitioned to the left and right of this camera. The cameras vfor the back row pins (7 through 10) are plaed above the rst row of cameras. Such positioning of the cameras produces reasonably uniform in size images o fthe pins, in the respective cameras, making the signals from the -various pins more nearly uniform. The cameras, thus mounted will not 'be subjected to vibrations as they would be if mountedon the machine. An additional advan- Y tage of such mounting is that the carriera is very unlikely to be hit by flying pins in this location. Referring now to Fig. 3, it illustrates therfront view of the camera. It is mounted inafbox 1 5 having two idemiai from plates 16 and 17. Piate 1 6. is provided with asingle pin-hole 18, while plate 17 is provided with three pinholes 19 .through 21; The pinhole'plates16 and v17 constitute the frontendS, or faces, of two .independent cameras, one camera,` with plateV 1 6 and pinhole 18 being used to focus the imageofthe upper portion V(the upper rounded end) of some particular pin on a mast 24, Fig.l 4, while plate 17 and pin-holes' 1 9 20 and 21 are used for focusing the general background alley illumination en the photeeethode used for eem,- pensnting the detecter against any inetnetions 'in illnnnnetien. 'Mask 254 ismenntesl en a metallic braelset (not Shewn) Wheh Snpnerts the. mask apprennately three ann-ners efen ineh behind @the pn-inelerlate 1e- Only'ene mask is need in @neef tbeeameras' .such an Camere V16 whichY is need fer detecting Vpin Vwebble and pin Presenee. ,The illnmnntien eetnpeinseitigv 'camera 17 dees not require the use af anyfmask- Mask, er grid, 24 is made 0f transparent basefmaterial, Snell, .as glass or cellulose acetate lm, with a l10n-transparent and pattern .2;5 nupempesed en the transperentbase. The PreferredV version O f the grid pattern," -Whieh' was found to produce maurirntnn amplitude variations, consists of a saw-tooth straight strips. lt has been found experimentally that such pattern produces fhe'most uniform amplitude signali from "all the pins located in variousV positions, 'and no pin .in the field ,of view of .the eanieraandthegrd .een move in any manner Wtnent a changein the tensity of the light tranemited through thelinask, 'Enns thereis ne Problem oferenteten of; themesk with respect to the pinimages. The widths. of 'the opaque strips, clear strips and sawtooth edge areV equal Y to Veach other.. The sawtootlrangfle is 45." The functionof the sawteotb edge en the mask isl tanerease the .Signal wave 26,*projectng beyond the produced by the foreshorteningof the pin image as ka pin wobbles back camera. Versions of this maskwith various-scale'factors are not critical as long as the mask Vis not so coarse asfto permit a pin to wobble without part of its image Y' moving out from behind an opaque strip into` the saw- `tooth, or clear area, and-not so ne Vas to lose signal and forth toward and away from the to Y'adifference circuit 32, the output Vof which produces 'ya wobble signal and a Ypresence signal. Y'Ihese'signals strength; .Thermark-sare alsoscaled 'so that the width of the opaque strips .at their narrowest pointsris made equalto the width of the incident image of the pin neck. In the illustrated version of the mask, the in- Y dicated dimensions a,`b and c are equal to each other.

It is to be understood that this invention is not restricted to theabove-mentioned configuration of the mask, and

otherV patternscan be used successfully so long as the aboverbasic.considerations .are kept in mind. Y

' The pinhole camera `10, illustrated in Fig. 2, uses a pinhole in eachncamera forfdetecting the .pinwbble and 'e e suiicierntly small to resolve Yp'uiesence. A pinhole lens,

Vthe Vhead of"r a Vbowling Vpinf-(inone"example, theV pin.V Y holes were '.03finch in Y e Y of lightfto'permit operationl ofthe'detectorY witha readiameter) admits suwicientr'amount 'sonably simplefand' inexpensive photornultiplierr circuitry.

. -A pinhole lens -isfsimplyra yh ole, Vot aY proper size and placement, drilled in `.asheet of "opaque material. The Y'pinhole lens, in addition to itsobvious advantage .of lowV Y cost,a'lso hasafjvide anglerarnd Yprovidesan image of f clarity, relatively independent of-v object distance becausel areused forYV timing the operation of the pinsetter. The eiect of light intensity uctuations, therefore, is Substantially cancelled out 'because both cameras are equally adected by the random uctuations inthe intensity due to Vvoltage uctuations. The photomultiplier load resistors are adjustedto,equalizetheV anode voltages in the two viewers, with all pins standing. VComplete cornpensation'of light changes "occurs onlyv when alll pins are standing.V `However,-` the useful signal has a suiiciently large amplitude for practicalpurposes.

In order to minimize the. eiect 'of the line voltage on Y the entire detector still further, it is desirable to use a regulated voltage supply which uses voltage regulator k 4gas lled tubes. Such'regulated voltage supplies Vare well known in the art and, therefore, need no furtherdescrip- "The outpu'tof the (inference circuitr32 produces two signals; one signal is the amplitude modulated signal correspondingY to theV pin wobble,` and, the second signal i is theleve'l modulated signal corresponding to pin presence and absence. TheseV areithe'previously mentioned A M. and LM, signals. The two signals are'both impressed on a presence amplilierY 33 where the wobble signal isfiltered lout so thatonly the L.M.V presence signal of Yan ininite depth of focus; thus the pinhole lens can Y Y befocused `onftheking pin or on the'rear'pinfandgits ieldof` view may becontrolled by varying between 'the pin hole and the photo-cathode. f Three pinillumination; .'Ifhepsensitivity of the the distance photomultipliertube is not forrn oyer Y,the cathodeV surface, but is highest in .the f central Y'region and drops rapidly toward the edges of i @holes are used in camerali? illustrated in Fig. 3 in order to obtana betterintegrationotrthe overallbackground hasanyretectzon a pin presence relay 35.Y The functions performed by this relay will be described later in .connection k,with the descriptionof the relay system shown in Fig. 14.V .Y l n.

VThe A.M. wobbleandiL.M.fpresence-signals are also impressed on 'the wobble signall 'channel which begins jwitha lovvjpass ilter 34, whereA higher-)frequency coml ponents .than ythose encountered inl pin wobble Zare ef-` fectively discriminated against'byYV this lterf. 4This filter,

l togetherV with other lteringelemerits, such ,as the low pass filter in therphotomultiplier circuit Vmounted in carnera 31, limit lthe"bandfpass Ycharacteristics of the circuit fthe cathode. Thisisprobablydue to ahigherrnultiplicar-V A tion'ibefingg; obtained` with electrons. Vleaving the central Y portion-ofV thelcath'ode than from thoseleavingthe cath,Y

ode edges. In order to obtain afreasonablyfgood signal -uniforrnityfromallthe pins, all individual pin camerasY .Y

Y .Y should focusftheepinheads on the centralA portion yof the .photocathode.v f VAll ofthe components of the detectorand fthesourcev 'of illunnination.v 30"areenergized- Vfrom an alternating Y currentfsource, which is Yused,` for providing electrical ever'a sudden load l,is -Vconnec'ted to thesource,it isfi'apt Vlfo'produce eithertransients .or variations :inY thej mag-V n itudeY of such voltage; orf-both,which are aptftofin- -uencefproper operation ofthe' detectors, ,j YI11.orcler to Y cancel lthele'iectv ofsuch transie'ntsy and iictuationsV ,in

' flus'tratedin Fig. 43,"Which is identical'to` the viewing, or n Y, camera, 16 usedfo'rproducing the wobble signalexeept tensityV ofiillumination @will generally occur whenjfsome Y fion Of 'f machina? f i Vlen'eig'gyfvfoi actuating'a'llftlie detectorsh-thelightsand Vthe motors'usedin connectionewith pinsetiter'sv.- When Yte .so thatthe"only spurioussignals which canzaffect the pin wobble detector, arethose with frequency components 'similare to those produced bypinmotion.` The eifects of longfrte'rmchangesin illuminationjforexample, are lild'out by YVcoupling capacito'rsin the vvwobble signal ch nnel,` while very rapid transients areremoyedby the impressed Von an*amp1ierl' 36,fand thenona rectifier and .Y limitercircuitfSS -fthe output of Ywhich is impressed on a sharp *cutoff pentode amplifier 40. .Theoutputof'pentode 40 energizes a'relay 42, which'has-armatures:43` and 44.

jArrnaturejA isused ,for controlling-'theV operation Vof fthe pentode, while armature is used frorlctiming the operation loffthev pinspotter'injthe .manner which'will be Y Ythe',.intensity of 'illumination,gth e detector'rfisgprovided withV the `compensatingviewingdaeadformcarnera, .17 i1- fdescribed-later in connection withthe descriptionv of the lrelay.` system shown ingFig. 14.1V :Relay 42 willbe called the wobble relay becauseit becomesfienergized in re-V Vsponsetof'pinwobble-jv As willzbelpointed out later, theV 'ynorrnally closed contacts 42aV oftenj'wobble relays are -corinecte'dfi'n serieswith Ithe main relay of thepinspotter Y. and, thereforre,1 thejpinspotterrelay is energized immediza'tely ifthere isno-wobbleror/its energization is delayed Yasdong asranyjo `the Yten .pins continue to wobble. The Y, yery .montent wobble,ceases,*relay142-;becomes cle-ener- Y gized,f;the'` circuit of the `'mainfpins'potter' relay. becomes :ing orispinning'ofthepins; In ,viewgof the absence of i mask Vf24firiheadl 177so'me` ldifierence in the overall fm1?.

trolled by the wobbling Y closed', the pinspottrfisput into operatiori.According ly, vtheV operationloff therpinspotter .isf` controlled by .theVV vwobble relays V4t2. :jThe're is anginstant' starting when -tliere-isV 'noVY wobble; the` length the' delayfbeing con- VReferring;to Fig.YL ',.rwhich'is the scheniatic ndiagram ito:'and'.inclinig1 relay 512,1, sie v,prieto munieive Y Ythe YwobbliandA lum ation V"signal,-

9 mination signal furnished by the pinholes 19, and 21 of camera 17. The respective dynodes of the two photomultipliers are connected to the respective common resistors 55 through 62. The dynodes 63 and 64 are grounded through a grounded conductor 54. The anodes 65 and 66 are connected to a positive source of potential 121 through a conductor 76, fixed anode resistors 67 and 68 and variable resistors 69 and `70, respectively. The cathodes 52 and '53 are connected to the negative terminal of a high source of potential 74, while the posi- Vtive terminal of this source is grounded. Condensers 71 and 72 are also connected to the respective anodes on one side and to ground on the `other side. Condensers 71 and 72 act as low pass filters and serve to reduce the 120 cycle per second signal which is the modulatton signal appearing on the anode due to the double line frequency ripple produced by the alley illumination. These condensers also reduce the anode modulation, which in Iturn reduces the linear dynamic range required of the difference circuitl operated by the photo-multipliers. The'variable resistors 69 and 70 are adjusted, so as to make the two anodes 65 and 66 vat the same potential with respect to ground when the pinholes in .two cameras are open and the pins are standing on the alley floor.

Since the corresponding dynodes of both photo-multipliers are connected together to the -taps on theV chain of the common resistors 54 through 62, some crosstalk signal is produced because of the use of the common dynodeV resistors; this crosstalk signal is largely cancelled out in the difference cireuit-and does not-significantly affect the overall operation of the pin wobblev detector. A further reduction in the crosstalk can be obtained by providing an independent chain of resistors for the photo-multiplier 51.

The output of the photo-multiplier 50 is connected through a conductor 73 to thegrid of a triode 75, while the output of photo-multiplier 51 is connected through a conductor 85 to grid 84 of a triode 77. Triodes 77 and 75 are conventional cathode follower impedance multiplier stages, and are identified as such by the fact that one terminal of the grid resistance 80 is connected to a tap 32 on the cathode load resistance 78-83 through a biassing e as compared to resistance 83. The direct current irnpedance seen from grid 84 to ground is several times the value of the grid resistance 80. `The same is also true of grid 86 and its circuit. Moreover, the impedance multiplying circuit has a high nputimpedance and, therefore, -does not reduce greatly the photo-multiplier signals by shunting them to ground. The cathode followers 77 and 75 have low output impedance and, therefore, long leads A8'! and 8S can be run ifrom the cathode followers to' the remainderv of the circuit which is mounted outside of the camera box 15. These leads are connected to the difference circuit 32 which includes a double triode 90 having its cathode connected toa common cathode resistor, 41. Grid 92 isconnected throughconductor 88,

resistances 93 and 95 and a biasing batter-y 96 .to the cathode of 'triode 77, while grid 96 is; coupled `to the cathode of triode 75 through conductor 87, grid resistor 98 4and a biassing battery' 97; `Grid 912, therefore, receives only the signal which represents the intensi-ty of illumination and variations in the 4intensity of illumination due to the voltage fluctuations, while grid l96 Vre-Y ceives thesignal proportional Ito the .intensityr of` illumination, and the variations in .th'e illumination, the wobble signal, and the presence signal;` Y'Ihre difference circuit,V

as its name implies, has :an output proportional to the difference of the signals from the `two impedance multipliers. The difference cireuit output -s thus proportional tothe difference in the-two signals `produced at the two photo-multiplier nodes. When `the intensity of-illumination iluctuates, corresponding'to aline 'voltage fluctuation, approximately equal signalsf are produced 'at the two photo-multiplier anodes, andthe outputofrthe battery 37. Resistance 78 is a high resistance ference circuit is very small. When .the pin moves, however, the signal produced at the anode of the masked photo-multiplier 50 is very much larger than that produced at :the compensating photomultiplier anode. It isealso of different algebraic signin a random fashion. A detailed desorption of the difference circuit is not necessary because the circuit of this type is known in -the art. Sufice it to say that the difference signal, corresponding to the wobble or presence signals, appears across a plate resistor 101. The positive signals impressed on grid 91 produce a positive signal on conductor 39, condenser 1&0 and the two cathodes. Plate 93A becomes more positive in repsonse to :the above because of the reduction in the space current.' Therefore, a positive signal is mpressed on conductor 39 and condenser 100. When grid 9,2 becomes positive, plate 93A becomes more negative because of the `increase in space current and conductor 39 and condenser 1130 receive a negative signal thus subtrac-'ting 'itself from the positive" signal Vproduced by grid 91.

` The wobble A.M. signal and the presence L M. signal both appear on conductor 3,9 and are impressed on condenser lil, which couples the wobble channel to the difference circuit, and on the control grid 151 of a pentode 150. The -wobble channel, through its Vcoupling condenser l-t and a low Vpass iilter condenser 1,05, eliminates lthe presence signal and trans-mits the A.M. wobble signal `for energizing .the wobble relay 42. V'l'he presence channel, inluding pentode @150, shunts to ground the A.M. wobble signal through a capacitor 152, but the variable -level signal, which may be regarded as a direct current signal, is impressed on grid 151 making pentode 150 more conducting. This increase in plate current energizes' the presence relay 35. Relay 35 is shunted by a capacitor 153 which improves the operationof relay 35Y by decreasing the difference betweenV the currents which are necessary to energize and de-energize relay 35.

Reverting once more to the wobble channel, the Wobble signal-is impressed on the control grid of a pentode ampliier 9.9 through capacitor 100 and resistors 103 and 104. The grid resistor 104 is shunted by a capacitor 105 the value of which is made so `as to act -as a low pass lilter to ground. VIn one example, resistor 104 had a value of l megohm, while condenser 105 has a value of 2 rnicrofarads.V Higher frequency components than those encountered in pin wobble are effectively discriminated against by this filter. This filter andthe other ltered elements, such as condensers 7-1 and 72, limit the bandpass of the circuit so that the only spurious signals which can aect the pin wobble detector circuitarethose with frequency components similar to those produced bythe pin motion. The effects oflongterm changes in illumination and the presenee signalsfor example, are filtered out by coupling capacitors in theA wobble lsignal channel while ver-y lrapid transients are removed by the "low pass filters including condensers V71, `72and1il5`.

Pentode 99 circuit, which is connected and operates as ClSsAamI-rlisr, includes a fired cathode. resister 106 in series with a gain control potentiometer 107. The

output of amplifier 99 is connected through a capacitor 10S toxa' detector and a limiter including' a diode '109 and 1.10- The detener. 110.9118 aangesteld across a resistor 111 and in series with a signal storage eapacitor i12-so that only positive signalsvirnpressed on plate113 makediode 169 conductive and, at the same time, charge up condenser 112 with the uplper plate ofthe condenser,

l which is connected to Ythe ontrolY grid 1149i a pentode ampliiier`1'15, vbecoming more positive y vs/hen diode 10.9

pentode 115 conductiv 'I'he second diode 110 actsV as a limiter of the positive signal impressed on grid 114 because itis yconnected across condenser 112 through resistors 116 and 117 and a conductor 11S. The two re- Vsistorsl 116 .andr117 act as' potentialdivider resistors ,COImeCtd between srvundsd scnductr 120-and a ,$911168 across condenser tion is no longer than for smallerV signals.V

, normally closed contacts 42h ofrel'ay 42.

of relay 42 is connectedrin series with.the plate circuit Y of pentode 115.

, -Y Y Y 11 i` Y .Y of ypotential'121. When the voltage impressed on the plate of diode llbecomes higher than the voltageim-Y pressed on its cathode by source 11Z1,diode 110 becomes conductive and 112 and,kas`a consequence, also limits the positive signal impressed on grid 114. Because of fcoil. In order to makeY this system as sensitive as posthus limits the potential that may appear the'` limiterv 1t)9-110, the time delay between cessation of Va verylai'ge signal and resumptionof pinspotter operaof limiter 110 is impressed The output c on grid4'11`4 of pentode`115 4whiclifhasra circuit to produce sharp cut-o. Cathode'139 of this YVpentode is connected to ground through resistors 134 and VY135 and a tap 117 between these resistors Yis connected over aconductor 136 tothe The left contactl42b' is connected di- 'Y The :Winding s to each` other.

sible, the two coilsrshould be placed as closely as possible The floor coilsV and the coil Yin Ythe'base `of thepin, nevertheless, should be Yrecessedsuiiciently so estoV permit the insertion of an insulating layer of suicient thickness which Ywould .protect` the coils from ordinary wear and'tear. The insulatingVV material suitable for Vthis purpose isV the Permabase plastics mate- Y rial described zingtheus. Parents 2,739,814 and assenza.

rectlyto eathode139 o vera conductor-137 andVV armature Y 42d is on contacts 42b when relayr 42` is not'V energized y Y and Vit opens contactsV 42b. when relay 42 is energized.

Thereforefwith no wobble signaLthe cathode resistor` 135 is shunted by armaturef42bresting on contactsi42b;

:A'oor coil may lconsist 'oa suitable number of turns of wire with a capacitor connected across Vthis coil to tune thecircuitto the operating frequency with the pin removed from the alley oor. Although the frequency range of vsuch system is not critical, Vthe ultra high frequency (UHF) andY the high frequency; range is less desirable because the lossesinthe surrounding mediumV Vat' these higher fre- Y quencies are larger'than -atvthelower frequencies.v On

the other hand the audio frequencies would require large` coils which areznotsuitable v'fromthepracticalpoint of View. Accordingly, the range of frequencies I'which Yis f most suitable for the systems of the above type is between Y 1GO Ylrilocycles and Zmegacyles.

shunting of resistor 135 reduces'the positive cathode bias on Vcathode .139 as'long V,as relay f 42 is `not energized.

' When relay 412 `becomes energized, the short circuit across resistor1,3,5 is Yremoved and it becomes connected Vin series with cathode 139. Thereforethe positivebias .on cathodel139-is increasedruponv energizationjof relay k42.

'.which'jdecreases -the magnitude-cof the Vgrid V'signal re#Y quired vfor de-energiaing relay 42 and alsordecreases'the Y Ydifference in gridrvoltage between the-level at which re- Y '12131142 iS energized and that at whichitis Vcie-energized.` t The relay winding 42Y is shunted by` a capacitor 123 forV eliminating contact chatter., Condenser 123 ispalso used forrhol'dingjrelay 42 energized if there Vis a momentary y, decrease inthe wobble signals below a predeterminedA level yby 'discharging'condenser '122, through winding 120. f Y Conductor 66 connects relay 4:2 to theV positive terminal When the pin isfplaced on the oor coil, connected to a sou/Ice ofV carrier frequency, and wobbled, a modulated carriersignal is produced.V Thefmodulated carrier signal acts las an indication of pin wobble. Moreover, an increase intheamplitudeof'the carrier @(level modulation,

of source 121. Conductoris also connected to-.con-Y `ductor -136 through a resistor 131, foi-obtaining proper Y j bias of 'p'en'toderllA74 A wobble signal, impressed onA giid y k144V is a Ypositivesignal and, therefore, Vit causes in-V crease inthe space currenrt, which,v causes agcu'rrent in-V 'identify 1the ,types 'of circuits which lare capableof per,-

crease `through `winding 42 and -Dfese in Gwent' mally tube 5115 is nonjconductive since grid 114 isiat l Vequivalent element,`iscthecoil Yinstalled inY theabase of ground.potentialcandgcathode 133 is at some positive potential Vdetermined by the valuesof theresistors134 f and=131 `which larefoonnected across the Vpowersupply` I S '121.1 Therefore, grid'114 is at a'negativepotential vwith ArespectY to cathode 1335 Y 5 f i Y f The wobblerelay 42 icontrolsf-theptimefof closingoiY the'.- pinspotterfmain Yrelay 302 since contacts 4241i and ill'tbe followed with.therlescriptionlof'the capa oil mounted-inthe alley'ilr5cir and a coiifmounted in the mentioned previously) is produced VwhentlreV pin is rev *moved-orV knocked over v"net :auseio'f'the decrease in the losses produced inthe Yoor, vcoilfiby vthepin coil. Ac-

cordingly, theamplitude modulated signal andchange in thelevelof the carrier signal,v maybe usedY for obtaining an indication of pin wobble and pin presence, respectively.

The wobble 'signal is obtainedvby detecting its Vamplitude modulation.V rille same-detector' canals'o be used to produce the carrier level outputfsignal,Y which is the direct current output, for indicatingithepresenc'erof"any indi- 'vidualpinQ VA'bloek diagrampfsuch system is illustrated in Fig. 7.- g The circuitsusedin the ,inductance pin wobble 'and'A pin presence detector are known inthe art and, therefore,tno schematic diagramstof. the circuits are necessary. -However, suitable 'specific circuitsrwill be mentioned in the, course ofthe description zof the-block diagrarn, to

`forming the intendedfunctions in the optimum manner.

. vReferring toV Fig? 6,; a coil 680, or an electronically a standardpinfMaXimum useful' signal i'sy obtained if rthepin coilis tuned. to theA VfItqll'eIitfy of thegapplied voltage.- The v,output Y signal may Ybe increased, for f example,

'ten-wtimessince it-`is relatively easytomake Q, or the I 1 figure 'of merit, ofthe kcoilz'equal to.V atleast ten;V .The pin Y Y coil mayfconsistfofaenough"-turnsbtwire'ittunelitwith` conductors` 155aand V156,are.connectedin series'with the J v main pinspotterrielayfas. will bedescribed laters-incon-l Vnection withthedescriptionof Fig. 1 4. I f 'A the vaid ofV a condenserY y601iconnected;acrossthe coil to 'the req'uencyi ofY thef oscillatoriused iorproducing the v Y carrier-frequency. Since each indu'ctance-coil has its own resonanceffrequency, Aitisalso''po'ssiblemto use only. a coil 1609 withoutany'use fecondenserortlhso' long fasthe c Vcoi-l is Lniafde resonant Tfatthe'carrier frequency.V VBowling .so

Y' plurality of `turns land Athe"electronicallyfequivalentelepinsof-tnis type,` providedzf'with asingle-tnrn coil; `or a ments; arel disclosed'more fully 1inl .the'pre'vio'uslyV menarci-tuned .to the same canienfrequencyand the tuned circuit @2f- 603 'is {c onnected, to`:a?!catl1'ode lfollower 6,04 Y, Ythrough a lresistor'16952angliaecondensergfttlt.j,ftWith the i y stated here each pin, are

later-detector and the coil is reduced to zero. Vsuch construction iscapable-iof increasing the signal level f required with the system disclosed in Fig. 6, only two channels being illustrated in the figure. A single oscillator 608, such as a tuned grid oscillator, is used for impressing the carrier frequency on the ten tuned circuits. It is preferable to have a crystal controlled oscillator to avoid frequency drifts and the loss in the sensitivity of the circuits due to such frequency drifts. Oscillator 6% is isolated from the tuned circuits by interposing an amplifierA 699 and a buffer amplifier, or a cathode follower, 619.' Ihe buffer amplifier 610 is connected to ten cathode followers 604 over a Vconductor 660 with each cathodefollower 694 being connected to the respective floor coils 692. Oscillator 698 Vthus furnishes the carrier frequency to the ten` tuned circuits. The output of the tuned circuits is connected over conductor 607 to a detector 611. The direct current output of detector 611 is connected over a conductor 612 to a direct current presence amplifier 613.' The signal impressed on. amplifier 613 represents theraveragelevel of the signal appearing in thebutput of detector 611@ This average level is con-A starit wheithe're is no wobble and its level is modulated when there is a wobble. .It increases greatly when the pinis absent. Y

The direct current presence signal (thepreviously men; tioned level modulation signal) is impressed on a presenceampliiier 613 through a metallic, direct current path by connecting the plate of detector 611 to the grid of the presence amplifier 613, the plate'resistor of the detector also acting in such case as'a grid resistor for the grid of the` presence amplifier 61.3. Amplifier 613 corresponds to the 4amplifier 33 in Fie. 2 and pentode 156 in-Fig. 5 and performs the same function as the above elements in Figs. 2 and 5. The output of the presence amplifier 613 is connected to the presence relay 35 corresponding to the identically4 numbered relay in Figs. 2 and 5f .The operation andthe control functions performed byrelay 35 will be described laterin connection with the description of Fig. 14. h Y

Theroutput of detectorrll is impressed on a wobble amplifier 621V which corresponds to the lwobble amplifier 9g inlig. 5 and amplifier 36 in Fig.r 2, A low pass filter 3ft may also be included inthe -wobble channel. In'general, the wobble channel in this detection system is identical to the wobble `channel 34, 36, 38, 40 and 42v of Fig. 2,- and the same channel shown in schematic form in Fig. 5. Condenser ,622 in -Fig6, therefore, correspends to condenser 163 in Fig. 1 5.' The wobble relay 42 in Fig. 5, therefore, performs the same function as the wobble relay 4 2 in the prior figures.

One of the advantages of the system disclosed in Fig. 6 is that it uses only one oscillator 608 for producing a carrierfreqnency for all tenchannels. At the same time, the use of one oscillator requiresa cmeful tuning of the door and pincoils 602 andtltl ,and capacitors 693 and 691. The system disclosed in Fig. 6 performs wellonce the ,tuned crcuitsin the pin .and inthe Adoor Iare properly adjusted. One additional Afactor which one should 'take into consideration inconnection withldigv. 6 is .that the length ofthe cable between the tuned circuit- 6102-603 and the cathode 'follow/eretta cause'sthefeiective Q, or d l eiig,1ire of, mrit,'of theoor coil to. bef lowerthan the measuredQ of coil 6,92. VThe operan'ngz-lcharacteiistics of the system disclosed inFig.` may be improved by1 providing ten separate oscillators withthe floor coils themselves being the "frel signals.

quency determining elements byinakingthese `coils "as ,an

integral partn of 'the4 oscillator with the oscillator and detector; mounted inthe center of thefloor coil form'.

In this manner the length ofthe cable between the oscilenouglrto` make the yprecise ituning of the Apin coils unnecessary..4 f :1I v

The systemof the. above, type illustrated inlFigs 7,

i 'uand `8..V 7: illustratesfablocl'rrdiagramofthe circuit,

l FiguresL v9 while Fig. 8 illustrates the schematic diagram of a suitable oscillating detector circuit'which-can be used for producing the individual carrier frequency signal and `detection of this signal in each Vindividual channel. The performance of the system disclosed in Fig. 7S Sllprior to the performance ofthe system'disclosed in Fig. 6, but it requires the placement of the oscillator detector circuit in the center of the door coil form and requires ten oscillator-detectors. This disadvantage, however, is more than compensated by the superior performance of the system. Y i i h Referring to Fig. 7, the pin coil-capacitor combination 700 is coupled, as before, to the floor coillcapacitgor combination '701 and the latter is connected to the oscillating detector circuit 702. The output of the oscillating de-v tector is impressed on a conductor V'703 to indicate the presence of the particular pin while `the wobble signal appears on conductors 704 and 705 which are connected to each other through a capacitor 706. Identical elements are used in each'channel for each pin and, therefore, there are ten channels altogether. grounded resistor 707 is used as a grid leak and also as an output impedance of the oscillating detector circuit illustrated in schematic form in Fig. 8. Conductors 703 are Vconnected to the individu-al presence amplifiers, suchA as amplifier 613 in Fig. 6, and amplifier 159 in Fig. 5, and the wobble signal, appearing on conductor 7435,is impressed on the wobblesignal channel identica-l to thatfshown in Figs. 2 and 5. Conductor-705 and capacitor 796, there# fore, correspond to conductor 45 and capacitor "100 1in Fig. 5. The relay system operated by the detector 'cir-f cuits of Fig. 7 is identical to the relay system oftheprioi' figures and that disclosed in Fig. 14.

Fig. 8 discloses the circuit of the oscilla-ting detector which can be used in blockp702 of Fig. 7 I'hewosci-llator is the Hartley oscillator. 'The pin-"coill 820 (with or without ya condenser S21) is coupled as closely as practicable from the point of 'view ofk wear and tearf tol the floor coil 82,2 which ,has a tap' 82?;"connected V to the cathode of triodev 824. Coil 822is sliunted by a condenser 825. The tuned circuit S22-825 is cdupled to the grid by a capacitor 8 26. Thegrid is also connected to ground through a resistor The presence,i anl the wobble signals areirnpressedy over a conductor 81,23 on the presence channelsirnilar'tofthat'disclosed previ# ously, and the wobble signals are impressed through capacitor on conductor45 twhich' correspond to the identically numbered elements in the prior'figres. When the pin coil is in the proximity of the ylioorcoil 82,2, the overall Q of the tuned circuit v.is notas high as when coil 826 is absent. frrccordingly, withv the standing, the amplitude of the oscillator is Vnotas high with pin absent and, therefore, thenmplitude ofthe Valternating signal appearing acrossresistor 327 is'notfas high with the pinstanding it is with the pinabsent. When the pin iS absent. the detector v Oscillf'te 'develops alarse negative grid voltage appearing tacross'resist'or $27 Vand this signal is impressed on the outgoing presence channel. The wobble channelfilters out such. s ignals, .t hrough the coupling condensers and the low pass filters described previously, and, therefore, the operatipn of the wobble amplifier 9.9, Fig. 5,"is not laffected l The circuits disclosed in Figs. Zand 8 are of detecting the wobble andprese'nce'of" w l l furm-sh two distinct signalstheamplitude: mbdulation wobble signalV and the llevel modulation presencesignal', which Vcan -be separatediil thiuelectronic chhnelsafnd then directed to the relayfcircuits of .t e typezillus'trat'ed Vin Fig. Y1A for controlling the operatic of thefpinspotter in the manner which Willbe described nn Y throng-1h13` disclos,eladditional:yersiinsv of the inductar'ice and capacitance `pinrvvobbleand pm ,presence "detectors `1which fuse a" Wheatstne1 bridge-for detecting the wobble and presence signal portioniof pin;1003l 'nested to`a carrier source Vwithout respondingand l pin presence dete produced by the Yindividual pins. Fig: v9 is a block diagram for such systems. The base of pin 901 is provided with arcoil or a-coil-'condenser combination if the Wheatstone bridge 902-903 is an inductance bridge.Y If k'the-bridge is a rcapacitive. bridge, the pin itself acts as a capacitive element'iand, therefore, conventional pinsmay Ybe usedtwithout the insertion of any additional elements in vthebase ofthe pin The bridge circuit is connected either to -a local oscillator or an oscillating detector of theV type shown in Fig. 8. IThe output of the bridge is connected' lto Van ampliiier 904v which impresses its output encon- Vlamlary 28, 1958, the latter lbeing also incorporated by ductor'39, condenser 100V and conductor 45 corresponding to the identically numbered-conductors in prior systems. Ten individual Vchannelsfare required for continuously d`etecting` the status often pins,A one channel for each pin; 1

Figs 10 Aand 1l illustrate the inductance systemnsing 'inductance coi1s'1000 in the yalley floor and an inductive? ring .1002 or ya coil or a permeable insert at the bottom V1005whose frequency may be VVIn allcasesthe bridgesy are coni reference as a part'of this disclosure.

Since this invention uses several phases of the functional cycle of the machine disclosed in the U.S. Patent 2,559,274, it is unnecessary to disclose here the overall ,structure of the machine; such structure is fullydisclosed in the above patentiand a more recent U.S. ;Patent 2,773,-

689, granted December ll, 1956. The same is also true fofv the relay system ldisclosed in 2,559,274, which discloses the overallrelay system for controlling the operation of the entire.ma chine. Accordingly,"Fig. Vl4iin .this application illustrates only the modications in the relay system disclosed in Eig. 4 of the Patent 2,559,274 andthe remaining `elements of the overall relay system'are omitted altogether. However,

the functioning of the Ventire relay vsyst'ernwill beapparent `to those skilled-in the art from the description of the r'nodications in. therelay-.system Vappearing in Patent 2,559,274'. In order vrto :facilitate theundeistanding of the Y description of the relayisystem, and` its relationship to Fig. 4 in Patent k2,559 ,27.4',tl1o seY elementsiof the relay in'the rangerof 50,000cycles per second and Z'Jnegacycles' per second 'as described previously.'V

Figs. 12 and l3 illustrate a capacitive bridge detector,V

or transducer; in sucfh'tr'ansducer, metallic-plates 1200 r and V 1201 larernounted in the or ofthe. alley in theV manner illustrated in YFigs-l2 and 13f to form. individual capacitors. In vsuch case a`pin;. 1300,' maylbe a conven- Vtional .pin V withV orV withoutl anyV metallic inserts i in .its

bottom portion; theV bottom v-por'tioncan `also bernadeV of the. plastics composition knownias VPermzfiljase mentionedpreviously. In eitherfc-ase,Qwobbleor absence of the-'pin produces van unbalance in thejinductance or capacity bridgesv and-this signalor signalsV arensed for controllingthe pinspotter in the mannerdescribed-belowi-' In summarizingthelsysitems using an impedance bridge,

VtheV inductive systcms'require that a mass of `p'errnealol-e suchv as an electrically conducting ring'V VorV af n by using anl alternating current bridge spotter-cycle. 'Suchtransducer the presence and the wobble signalseoil. indnctance is measuredV continu- 5 ously. The absencelof a pin causes a reduction-in the amplitude ofthesignaLjwhile-a.wobbling' pin produces a closed andbecorne open only when'r relays 4 2 receive Y amplified yandused to control the pini 4 and the pit switch systemofFig. 4 Eig. 14, bear thes'ame identifyingnumer'als as those used Yin the patent and such elenie'nts;,forV a moreready identiication 'are put inV quotation marks.V For'example the pit switch f300 indicatesthatit is identical yto the identicallynumbered switch-300, in Eig. V4.0i the patent.

ously that the 'wobblerelay contacts'42a` normally are wobble signals.l Accordingly,'these relays can control the starting time ofthe entirelmachineby oo rmectingtheseA ten wobble relays 'in series `with theirnain relay 302 30W-"in Vthe 'manner indicated in 14. A source of potential `'1400 is connected in series with conductors and' the winding yf-relay` 7302.. circuit of the main tor '301a,f normally closed 'contacts 42pr Vof vt'enwobble relays .Mr-4210,' conductor' 3(01, andgrounded winding of relayl 302.V "which closes the entirfcircuitj through the "grounded "terminal `of. 'source .1400;Y The pitswitch becomes closed immediately after; it is Ystruck by a ball;

modulated signal. l The two .types of signals are separa-tedV in the :mal-:trierk described pr`ev ious ly in )the two channels.

The4 knockedover'pins will produce 'onlyf V fa very -small inductance change whenyr'olling'or-spinning "on theV iloor VV andgtherefore, Ythesystems of. this type can be Vmade to `interruptV thev fpinspotterlcyele V'when are wobbling tothe .rolling or spinning pins. VV 1 The same Yis valsojtrueof thesysteinusingv a capa'oitancek l1bridgeniumatedinnig- 12; 7

atent is*V afast-actingrelay -asdterentiatedgfr Y 'I 'herelay syst/em forcontrolling"the loperationof .a ipinsetting machine is disclosed in' Fig 14;- The disclosed normaloperation inventionv are YValso applicable to the machines ctalgn'se lvyriienffe; exampigare described; in l.: "paraY u1 Produet nngineeijngafiinj '1954 issue, andy e RogersE,Dmas-application-for.patent S.N.-22 '6, 559 g therefore, after switch f00telesesgthe"energization of the abovecircuitii's controlledy only by the ten serially- Y connected wobble, Vrelays-4 2. Y Y Accordingly,""the entire icycle ofthepinsetter nowcontrollednbtenlyy'the closing of the Vpit switch 300, `as' 'clisclosed fin.`the aboveY fpatent, but alsqlgyf theten wobble elays'Zi-'fl-Zlo, any

one offwhich VViscapable of-d'elayingith V n machine tliewobbleeases, where relays 42 becon "1e de -energi zed, .con tacts 42a f ,becorne closed,' and the operatiornof, the naehine takes place the very moment the wobbleceases:Y 'Relay302,"tlierefore,

omhtheff delayed closing relay 3.02;` in ,the r aboye'pate t Once the relays 4 2 arejall closed, whenallwoljble'cease, the' v Y Yallc'lwed to operate'v'vith'out any otherdeia When kthere v is'nofwobble, thefnachine is permitted tooper'ate irn- '5 meditely afterg ball strikes pi switch .ff3 00 and he f ast- ,acting 'relayf isfeiielsized; Thtrrifil11'?0f the Y identical to that disclosed in ith-thernodications which repointed Yh areeau'sedby the :preventionfof Yitsl machine, from then. o

L out below, and

7fas' wellias thefsecondfbal are`-botl1gutter2ballsj; I

Fig. 4 ffo'f the' Patent t of the patent, which lare also shown in f wobbl'e de tectiiivga.V systems Vhas been described preyiously.j ,-It alsoghasbeen stated previ- 5301,75 30111,'VA wobble relay .contacts 42a I Y operation offth 'i nitheaffected lmachine is (iyWhn menaient-1s guai-,remimienne-afn eau it follows that the initial starting of the machine is now controlled by the pit switch 3 00 as well as ten wobble relays 42. There is an instantaneous starting of the machine when there is norwobble after the tirst or the second ball or any other ball, yand `a variable delay starting if there is a wobble, in which case the machine is started immediately after the wobble ceases.

Pin presence system rPhe pin presence signal is impressed on a direct current amplifier 33, Fig. 2, and then a pin presence relay 35, -which is provided with three sets of contacts 35a through 35sl vall mounted on a relay armature 35d. The normal position of this armature, corresponding to the bowling pin standing on the alley lloor, is that illustrated in Figs. 2, 5, 6, and 14. Contacts 35a are open and contacts 35b and 35o are normally closed with the exception of contacts 35b on relays 357 and 3510, which are normally open and are connected in parallel by means of conductors 1401 and 1402. All the remaining contacts 35b are normally closed with the pins standing and are connected in series with each other and conductors 1401 and I1402. Conductor 1403 is grounded and conductor 1404 is connected to cam-operated contacts 35d and 35e which are closed and opened by a cam 35 having the contact-closing portion 1405 extending over approximately l60l70 of the cam 35f. Cam 357c is keyed to a shaft 255 corresponding to the similarly numbered shaft in the patent. It is the electrical control cam shaft on which all electrical lcontrol cams are mounted, as described in col. 8, lines 62-75 and col. 9, lines l and 2 of Patent 2,559,274. As stated in the above description,

the control cam shaft 255 makes only one revolution forv every two revolutions of the main cam shaft 28 and is driven by shaft 28. The control cam shaft 255 makes one revolution for every two ballsand one half of 'a revolution for the rst vball and the remaining one halfrevolution for the second ball. Contacts 35b of the presence relays 35 are that set of contacts which are used for eliminating the operation of the pinsettng machine when only =pin #7 or pin #'10 `are knocked out by the -first ball and all other pins remain standing. AS mentioned previously, it is unnecessary to lower the table and reset the pins under the above conditions since the remaining pins are standing in proper manner and positions and, therefore, are immediately ready for rolling the second ball. 'T-he series circuit lwhich controls the operation of the machine under the above conditions is lgrounded source 1400, conductor 1405, winding 1406 of the relay having two sets of contacts 140611 and 1406b, conductor 1407, contacts 35e and 35a', which are closed during the rst ball play, conductor 1404, closed con tacts 3511 and grounded conductor 1403. Contacts 35b remain closed as long as pins l through 6, 8 and 9 are standing and contacts 35h? or 35b10 become immediately closed if either pin #7 or pin #10 is knocked down by the first ball. Closing of contacts 3567 or 35510 completes the circuit and this energizes relay :1406. When relay 1406 becomes energized, contacts 1406a open which prevents energization of the clutch relays 360 and 1408 which prevents the lowering of the table. Relay 360 corresponds to the similarly numbered relay in Patent 2,559,274 and, as described in the above patent, it is used for actuating clutch K-4. This prevents lengagement of clutch K-4, and thereby prevents the setting of new pins but allows the machine to operate and return,

the ball to the player. The functioning of clutch l-4 per se iu the machine disclosed :here is identical to the,

functioning of clutch K-4 in the patent'. The ditference resides in the interposition of relay 1406 which prevents the actuation of rel-ay 360 when only pin #7 or pin #l0 is knocked out on the lirst -ball and when the lirst ball is a gutter ball and the second ball is also a gutter ball. The circuits of all clutch relays, such as K-l, K-Z, and K-3, are identical to the circuits inthe patent and, therefore, need no description. The circuit of clutch K4 differs only in yoneY respect; i.e., an additional control relay 1406 has been -connected in series with the following circuit: -a grounded source 1410, conductors 1411, 1412, contacts 36in of relay 361, conductor I1413, contacts 140611, conductor 1414 and grounded winding 360. With the exception of relay 1406 and contacts 140611, this circuit is identical to that in the patent and normally performs the same function as long as contacts 1406a remain closed. The circuitry and the functions performed 'by relay 361 remain the same as those in the patent.

Reverting once more to the electrical control cam shaft 255 and contacts 35e and 35d, it is necessary to include these cam-operated contacts in the circuit of relay 1406 because this relay should be operatedby the closing of the contacts 35b10 or 35127 only after the rst ball of a frame has been rolled. Shaft A255 and cam 35i open contacts 35e-35d lafter the rolling of the second -ball 'and thus permit the normal operation of the machine after the second ball even if only pin #7 or pin #10 are knocked down by the second ball and all the remaining pins are standing.

Gutter baIIs.-It has been stated previously Vthat the disclosed rel-ay system prevents needless operation of the machine when the first ball is a gutter ball and when the first and the second -balls are both gutter balls. The above is accomplished with the aid of the presence relays, their second set of contacts and two gutter switches which also control the operation of relay 1406 in the manner described below.

The -second set of contacts of the presence relays'351- 3510 are contacts 35C. All contacts 35e are normally closed as long as the pins are standing, and are connected in series with source 1400, conductor 1405, winding 1406, conductor 1414, contacts 35C, and two gutter ball switches 1415 and 1416, which are connected in series-with contacts 35C and in parallel with respect .to eachother. Source 1400 supplies power to Vrelay 11406 and energizes it -when either the first ball or the rst and the second balls are gutter balls. Accordingly, contacts 35e'and gutter switches |1415 and 1416 control the operation of relay 1406 which is normally rie-energized because of the normally open position of the two gutter ball switches 1415 `and 1416. Operation of clutch K-n4, therefore, is also prevented when the first ball is a gutter bali-and when the rst and the second balls are gutter balls.

IFigures l5 and 16 illustrate the type of gutterl ball switches 1415 and 1416 which are suitable for performing the function assigned to them by the relay system. Fig. 15 illustrates the positioning of the switches at the inner ends 1500 and 1501. of the two gutters 1502 and 1503. The switches include collars 1504 and .1505 Whicr are supported in an elevated position above the .gutters by springs 1506 mounted in dash-pots 1507. The dash-pots,

tted with suitable uid, furnish su'icient time delay to maintain the contacts `1415 closed for that period of time which is required for preventing energization. of clutch- K-4 after the gutter ball. strikes pit switchl .300 andV puts the relay system into operation for one cycle of operation required either after the lirst or the second balls ofaframe. f n

From the description of the gutter ball circuits, it

follows that it is made operative -only if all the pins remain standing, all relays 351-3510 remain de-energized, and all contacts 35e remain closed. Opening of any contacts 35o, which takes place if any of the pins Iare knocked down, Vmakes the gutter ball circuit inelective, contacts 1406a .remain closed, and the machine is allowed to `operate in its usual manner, as described in.,

of the presence relays 35V;

. 19 ,other and have independent contacts 35b and 35e on'the presence relays 35. The ygutter ball circuit is not affected by the operationof cam 353c and contacts ,35e and 35d.|`v

Clutch K-5.'-In theV cycle ofthe pinsetting machine disclosed in Patent 2,559,274, the operation ofthe pin carrying grippers 68V of the transfer device N'are moved by cam 128 back and forth once each cycle of the machine, as described in col. l0, lines 44-54. -As also described in col. 7, lines 26-40 ofthe patent, the movement of table T to and from the pin supporting bed of the alley for setting and/or resetting pins is also effected by means of a cam 148 which is V-forrned integrally withcam 128, both of these cams being mounted on a cam shaft 28. In order to Ypreserve the function of these two cams in the normal oper-ation of the machine described inthe'patent and also adapt their functioning to the modiied cycle disclosed here, an additional clutch K- has been mounted on shaft 28. This clutch, and its solenoid winding 1408, are identical to clutch K-4. The circuit of solenoid 1408'is'identical tothe circuit of solenoid 360 of clutch K-4, the two solenoids being connected inparallel to conductor 1414.V Therefore, the two solenoids are'operated at the Sametime and under the sameconditions Ywhich produce the energization of solenoid 360. In'view of the above, clutch K-4 may be used for not only clutching and kdeclutching cam 74 to'and from shaft 28, but also for clutchingl and declutching cams 128 and 148 to and from the same shaft. Accordingly, the opera-tion of the pin grippers 68 and the movement-of table- T is now also'under control of the gutter ball circuit and #7 or #l0 pin circuit; i.e., it is' under control of the presence relays S51-3510 and gutter switches-1415 and 1416.

Y Pnfrzll signalling I VThe presence relays 35i-35m and their contacts 35a are also used for operating the pinfall signallingrlights l1 through10, Fig.V 14, corresponding tothe pin positions l through l0. In Patent 2,559,274, the pinfall signal lights are operated Vby means of respotting cups 112 which `are provided with the switch actuating members 3720 `which are Vraised in respotting cups .112 and close contacts 321 and circuit 322324..

V3`26b, and 326C. The closing of contacts 326a-1ightsa signal lamp (1-10) corresponding to the position of theparticularjpin ,which remained standing. The pinfrall 20 i by-relay 38,'it follows that relay 38 prevents the operation ofV clutch K-4 when (a) Yonlypin #7V or'pin #l0 is knocked down by the first ball, and (b) when the -rst ball is a gutter ball and when both balls are gutter balls.

Since clutch K-4, when energized, connects cam 7.4.t0

shaft 28, cam 74 remains inoperative and frame M and table T remain stationary as long as clutch K-4 remains de-energized. Therefore, switch 298 'also remains in its open position because switch 298 is closed byV cam 168 only when the table reachesitslowermost or pin-engaging position, Vas explained in col. 7, lines -50 of the patent. In order to preserve the normal functions of the machine, even when operation of clutch K-4 and loweringrof table T -does not take place because oftheV operationof relay 1406, relay 1406 is provided with contacts 1406b which close when relay 1406 Y becomes energizedl and .by-pass switch298.l l What is claimed as new is: i

l. A pin-setting machine for setting, removing and resetting bowling pins on an alley door in a triangular playing arrangement, said 'machine' including detecting means for producing a rstsignal in response to a-movement of anyindividual pin, said detecting means also producing `a second signal in responseto removal of -any individual pin from its normal standing position on .said alley floor, and mechanism Voperative in responsive-to said signals for controlling the operation of said machine in accordance with a predetermined sequence of operations.

l2. In a pin-setting machine for placing a new set of pins on a bowling Valley andremoving fallen pins, said machine including -a detection system forV said vpins, said detection system having means forproducing a first signal in response to a wobble ofany pin 'and a second signal in response to the knocking down of any pin, Iand mechanism operative in responsesto said signals for controlling the operation of said machine in accordance with a prey determined sequence of operations.

A Closing of circuit 322- 'Y 324 energizes relay 326 which closesY contacts 326:1,

signal relays 326 nremain locked in for the remainder of y the cycle, after .which the Vlight circuits are broken by they de-energization of relays 326 through'the opening of cam .contact .362a (not shown in Fig. 14 but shown' in Y Fig. 4, ofthe patent) mounted on shaft 255. De-ener-V gaization of relays 326 extinguish'es the pinfall signalling' lights thus completing the pinfall signalling cycle for any given ball.

In; the disclosed system, the-information about the presenceor absence of ythe pins is furnished by( the presenceV y relays 35 immediately after any particular pin is knockedl down. When a pin is knocked down, the presence relay 35cm-responding tothe knocked down pin becomes energized and contacts 35a, corresponding to contacts 323 in the patent, become closed and the corresponding relay 326.becomeis energized. From then on, the operation of the pinfall signalling means described'h'ereY is-identical to thatV in the patent. Accordingly, while in the patent the pinfall signalling mechanismy is operated by the respetan-,cnt 112,.in this case the pintan V"signalling mechanismis operated by the presence relays 35 directly. Therefore, 4the rrespotting cups 112 need not have any switches V3204-323 accordingto'this invention since they are replaced by the cont-acts 35a and armatures 35d ,comers 14061 v'of relay 1406 Y 3. In a pin-setting machine for performing the duties of a pin boy, said machine having a detectionsystem forv each pin used in a setof pins, said detection system having iirstmeans for producing kan Vamplitude modulation signal in response to a wobble of the respective pin, second means for producing a level Ymodulationsignal in response to removal of the respective pin from fits normal standing position, and mechanismoperative in response to said signalsfor controllingtfie operationfof'said machine in accordance with a pre-,determined Vsequence of operations. v

V'4. In a bowling pin-setting'machine, a detection system having Va plurality of transducers, one transducerY for each pinused in a bowling game, each-transducer producing a firstelectrical wobble signal inresponse to a wobble of, -aj pinV and asecond electricaljpin-pre'sencesignal in response` to knocking down of said pin, iirst andsecond electronic control Vchannels having their input sides connected Ito said transducer, said first control channel having means for rejecting said pin-presence Signal and ac-V ing game, said transducer having means for producing Y an electrical wobble signal in response to Aa wobble of the. pinV assigned to said transducer and an electrical presence signal in response tothe removal of saidassigned pin from its upright position, first and second control channels connected to said transducer, said first control` channel having means for by-passing said -wobble signal and amplifying only said presencersignal, and said-second control channel having means for by-passing said presence signal and amplifying only said wobble signal, and mechanism operative in response to said signals for controlling the operation of said machine in accordance with a predetermined sequence of operations.

6. The automatic bowling pin-setting machine as defined in claim in which said transducer is an opticoelectric-al transducer having means for converting reflected light from said pin into said electrical wobble signal in response to lthe wobble of said pin, and `also converting the retlected light into said electrical presence signal in response to the removal of said pin from its normal standing position in the course of. a bowling game.

7. The automatic bowling pin-setting machine as delined in claim 5 in which said transducer comprises an optical viewing device having in its view a selected portion of said pins when said pins are in their normal upright position, a member within said optical viewing device having alternate sections of varying light transmission, and a photoelectric element adjacent to said member for converting the light transmitted through said member into said signals.

8. The automatic bowling pin-setting machine as dened in claim 5 in which said transducer comprises a pin-hole camera, a photo-electric element having the image of said pin focused on said element by said camera, and a grating between said pinhole and said element, said grating having alternating transparent :and opaque areas for converting the wobble of said pin into a light signal.

9. The automatic bowling pin-setting machine as defined in claim 5, in which said transducer comprises an electrical impedance element operatively associated with each normal pin position, and a source of carrier frequency coupled to said impedance ele-ment, said impedance element producing said wobble and said presence signals in response to a selected condition of said pin.

l0. The automatic bowling pin-setting machine as delined in claim 5 in which said transducer comprises a capacitance element operatively associated va'th each normal pin position, and a source of carrier frequency coupled to said capacitance element, said capacitance element producing said wobble and said presence signals in response to a selected condition of said pin.

11. The automatic bowling pin-setting machine as dened in claim 5 in which said transducer comprises a rst inductive coil mounted in the base of said pin and a second inductive coil mounted in the floor of the alley Under ythe normal standing position of said pin on said door.

l2. The automatic bowling pin-setting machine as defined in claim 1l, which also includes a first capacitor, connected across the first coil, and a second capacitor connected across the second'coil, a source of carrier frequency coupled to said second coil, said irst coilcapacitance circuit and said second coil-'capacitance circuit being both tuned to the frequency of said carrier frequency.

13, The automatic bowling pin-setting machine as deiined in claim 5, in which said transducer comprises a trst resonant circuit mounted in the base of said pin, said first circuitincluding capacitive and inductive reactances, an oscillating detector having a second resonant circuit including a coil and a capacitor shunting said coil, said coil being mounted in the alley oor under the normal standing position of said pin, said coil being inductively coupled to said inductive reactance.

14. The automatic bowling pin-setting machine as dened in claim 5, in which said transducer comprises an electrical impedance element operatively associated with the Anormal standing position of said pin, an electrical bridge circuit, and a source of current connected vacross said bridge circuit, said impedance element being one leg of said bridge circuit, and an output circuit connected across said bridge circuit, said wobble signal and said presence signal appearing in said output circuit, and said iirst and secondcontrol channels being connected tovsaid output circuit.

15. The automatic bowling pin-setting machine as dened in claim 5, in which said transducer comprises Ian inductive element mounted in the base of the pin, a coil mounted in the alley oor under the normal standing position of said pin on said alley floor, a capacitor con-v nected across said coil, an inductance bridge circuit, a source of alternating current connected across said bridge circuit, an electrical circuit for connecting said coil and capacitor to said bridge circuit as one leg of said bridge circuit, and an output circuit connected across said bridge circuit, said tirst and second control channels being connected in parallel to said output circuit. v

16. The automatic bowling pin-setting machine as defined in claim 5, in which said transducer comprises a capacitor mounted in the alley door under the normal standing position of said pin on said alley iloor, a capacitance bridge, a source of alternating current connected across said bridge, said capacitor constituting one leg of said bridge, and an output circuit connected across said bridge, said rst and second control channels being connected to said output circuit.

17. An automatic bowling pin-setting machine cornprising a detection system, said detection system including a transducer for each pin in a set of pins used in a bowling game, said transducer having means 'for producing a rst electrical signal in response to a wobble of its pin and a second electrical signal in response to knocking down of its pin, a wobble signal channel yand a presence signal Vchannel connected to each-transducer, a wobble switch means on the output side of said wobble signal channel, and a presence switch means on the output side of said presence signal channel, said wobble signal chan-v nel being responsive only to the wobble signals, and said presence signal channel being responsive only to the presence signals. p

18. In a device for manipulating a pluralityof movable freely standing members, said deviceadapted to perform a series of selected manipulations, apparatus for controlling the operation of said device comprisingmeansfot determining the upstanding condition of each ofvsaid members, and mechanism operatively associating said determining means with said members and said device including means operative in response to the movement of one of said members within pre-determined limits from its freely standing position, to -actuate said determining means to control said device and cause said device to perform a selected manipulation.

19. In a device for manipulating a plurality of moveable members, said device adapted to perform a series of selected manipulations, apparatus for controlling the operation of said device comprising means for determi-ning the condition of said members after a first event, andmeans associated with said determining means operative. to control said device to cause said device to perform a selected manipulation in response to a change in condition of at least one of said members Within pre-determined limits as a result of the occurrence of said first event.

20. The invention as dened in claim 18, wherein said determining means is a detection eld. l

21. Inv a device for delivering a plurality of freely standing members to selected positions on a support surface, the combination of means for controllingpthe operation of said device, apparatus for determining the standing condition of said members including detecting means for detecting the movement of any said members from itsY selected standing position on Said support surface, and4 mechanism operatively associated with said detecting means and said control means; means operated by said detecting means in response to a movement of any of said members to vary the operation of said mechanism in a iirst manner when said movement is beyond predetermined limits, said control means being responsive to said variations to control the operations of said device.

'passive to an active state.

23 22. VvIn a machine for manipulating a plurality of movable freely standing members, said machine having active 'and passive states, means operative to control said ma- Y 23. A detector for deter i' g theV standing condition of aplurality of movable 'eely'standing members posi- Y tioned selectively on a support surface, comprising a detection field wherein said members are located, said detection eld co-acting with said members, said field V"being varied in a rst manner corresponding Vto one condition of any of said members and` in a second manner Ycorresponding to a second condition of any of said members, kand means associated with said members and responsive to said variations -for producing signals representative of said variations. s 1 24; A detector for determining the standing condition of a plurality of movableI freely standing members positioned selectively on a support surface, comprising a detection eld adapted to co-act with each of said members at its'selected position, said field being varied'in a first manner corresponding to one movement of any of members,VY and means associated with each member and said members on its selected position and in a second manner corresponding to a second movement of any of-said responsive to said variations for producing signals repre- Y sentative of-'said variations.

25. A detector for determining the standing condition of a plurality of movable freely standing memberspositioned selectively on a support surface, comprising means for establishing a detection field, said field adapted to co-act with each of said members at its selected position,

said field being varied in response to the wobbling of any of said members and means associated with said members and responsive to said variation for producing a signal representative of said variation. A

26. The invention as defined in claim 25 wherein said last-named means includes. an electrical impedancev element for translating said variation in said detection field into a signal representative of said variation.

27.y The invention as dened in claim 25, Lwherein said last-namedv means includes `a Vcapacitance element for translating said variation in said detectionfield into a signal representative of said variation.

" 28. VThe invention as defined in claim 25, wherein said last-named means includes 'an inductance element disof said members, "and wherein said members are'provided with a material which co-acts withY said indueta'nce ele. ments tovary saidv field in response to the wobbling, of any of said members to produce said signal. v

Y V29. Therinvention as defined in claim,V 25, wherein said last-named means includes an opticoelectrical transducer for converting reflected light from said members into an electrical signal. Y. Y

y 30. Controlapparatus for a bowling pin spotting machine, 'wherein said machineis adapted to place a plurality of bowling pins in pre-determinedplaying arrangement ona bowling alley, comprising detecting means independentl of said machine for determining a plurality ofstanding conditions of pins on said alley and disci-imi` natng Vmeans associated with said detecting means and operative to selectively control the operation of said machine in response to a particular standing condition of said pins.

' trol the operation of said machine in accordance with the variations of said field. Y

. 32.` 'Control apparatus for a bowling pin'spotting machine yadapted to set, remove and reset bowling pins in a pre-determined playing arrangement on the surface of a bowling alley comprising ay detection field for detecting Vthe movement of any of said pins on said Yalley after the first ball of a frame has Vbeen rolled, said detection field co-acting w-ith each of said pins Yand varied in a rst manner in response to the wobbling of a standing pin on its selected spot on Vsaid alley and in a -second manner corresponding tothe absence of Ya'pin therefrom and means kassociated-with said field and operative lto control the operations of said machinein a response to said variations.

33. The invention as defined in claigrn 31, wherein said detection field is an electrical field.

V34. The invention as detined'in claim3l,.wherein said detection field is an illuminationfield.

35. In a bowling pin spotting machine adapted to set, remove and reset a pluralityof bowling pins in a predetermined playing -arrangement on a bowling alley, a detector for determining lthe condition of said pins on said alley comprising meansY for establishing *a detection field co-acting with each of said pins at its selected position, said field being varied in a first manner corresponding to one movement of any of said pins and in a second manner corresponding to -a Vsecond movement of any of said pins, and means individually` associated with each pin and responsive to said variations to produce a signal representative of said variations.

36. In a bowling pin spotting machine adapted to place a plurality of bowling pins in a pre-determinedY playing arrangement on a bowling alley, a detector for detecting the movement of any of said pins on said alley after the first ball of a frame has been rolled comprising means for establishing a detection field co-acting with each of said pins at its'selected position, said field beingrvaried in response to -the wobbling of any of said pins and means associated with said pins and responsive to said variation Yto produce a signal representative of said variation.

37. 1n a bowling pin spotting machine adaptedrto set, remove and reset a plurality of bowling pins Y,in a predetermined playing arrangement on a bowling alley, a

detector for detecting the movement of any of said pins after the rolling of the iirst ball oa framecomprising a detection field co-acting with each of said pins Vat its selected position, said field being varied in response -to the absence of a pin from its selected spot and means associated with and responsive to said variation-to produce a signal representative of said variation. Y

38. The invention as defined in claim36, wherein said last-named means .includes an electrical impedance element for translating said variation in said detection field into a signal representative of said variation. l

39. The invention as defined in claim 37, wherein said last-named means includes an electrical impedance element for translating said variation in said detection field into a signal-representative of said variation. 4

v 40. The invention as defined in claim '36, wherein said last-named means lincludes a capacitance element for translating saidV variation in said detection'field into a signal representative of said variation. Y

- 4l. The invention as definedin claim 3.7, wherein said last-named means includes a capaci-tance element for translating said variation in said detection field into a signal representative of said variation',

42. The invention as defined in claim 36, wherein said last-named means includes an inductance element disposed in the surface under the selected spot foreach of said pins and said pins are provided with material which coacts with said inductance elements tovvary said tield in response to the wobbling of any of said pins to produce said signal.

43. The invention as defined in claim 37, wherein said last-named means includes an inductance element disposed in the surface under the select-ed spot for each of said pins and said pins are provided with material which co-acts with said inductance elements to vary said field in rei sponse to the absence of any of said pins to produce said signal.

44. The invention as defined in claim 36, wherein said last-named means includes an opticoelectrical transducer for converting reflected light from said pins into an electrical signal.

45. The invention as defined in claim 37, wherein said last-named means includes an opticoelectrical transducer for converting reflected light from said pins into an electrical signal.

46. In a bowling pin spotting machine adapted to place a plurality of bowling pins in a pre-determined playing arrangement on a bowling alley a detector for detecting the movement of a pin on said alley after the iirst ball of a frame has been rolled, comprising a detection eld coacting with each of said pins at its selected position, said field being varied in a lirst manner in response to wobbling of any of said pins and in a second manner corresponding to the absence of a pin from its selected spot and a transducer associated with each member and responsive to each of said variations for producing a signal representative of said variations.

47. The invention as defined in claim 46, wherein said transducer comprises an impedance element for translating each of said variations in said detection field into a signal representative of said Variations.

48. The invention as defined in claim 46, wherein said transducer comprises a capacitance element for translating each of said variations in said detection tield into a signal representative of said variations.

49. The invention as defined in claim 46, wherein said transducer comprises an inductance element disposed in the surface under the selected spot for each of said pins and wherein said pins are provided with material which co-acts with said inductance elements to vary said ield in response to the wobbling or absence of any of said pins to produce said signals.

50. The invention as defined in claim 46, wherein said transducer comprises an opticoelectrical element for converting reflected light from said pins into an electrical signal.

51. In a bowling pin spotting machine for use with a bowling alley having a pin supporting bed and a device for spotting and respotting pins on said alley bed, detecting means for producing a wobble signal in response to a wobble of any individual pin standing on said bed after the rolling of a ball, and means operative in response to a wobblesignal caused by a wobbling standing pin for preventing movement of said device towards said alley until said wobbling pin has reached a pre-determined state of equilibrium.

52. A bowling pin spotting machine for use with a bowling alley, said machine having a spotter for spotting and respotting bowling pins on the playing bed of a bowling alley, comprising detecting means for producing a wobble signal in response to the wobbling of any individual pin as the result of being struck by a rolled ball or by other bowling pins moving thereagainst as the result of the rolling of the ball, operating means for said detecting means, mechanism for effecting the movement of said spotter to and from the bed of said bowling alley, and means operative in response to the operation of said wobble detecting means caused by the wobbling of a pin for interrupting the normal movement of said mechanism after the rolling of a ball until said wobbling pin has reached a predetermined state of equilibrium.

53. The invention defined in claim 52 wherein said detecting means comprises a capacitance element operatively associated with each normal spot position, and a source of carrier frequency coupled to said capacitance element, said element producing said wobble signal in response to the wobble action of a pin resulting from its being struck by a rolled ball or by moving or fallen pins resulting from the rolling of a ball.

54. The invention detined in claim 52 wherein said detecting means includes an electrical impedance element operatively associated with each pin spot position thereof, and a source of carrier frequency coupled to said mpedance element, said impedance element producing said wobble signal in response to the wobbling movement of a standing pin.

55. The invention defined in claim 52 wherein said detecting means comprises an inductive element located in the base of said pin and a co-acting inductive means mounted in the bed of said bowling alley directly under the normal standing position of said pin on Said alley bed.

56. An automatic bowling pin setting machine comprising a detection system, said system including a transducer for each pin in a set of pins used in a bowling game, said transducer having means for producing an electrical signal in response to a wobble of its pin, a wobble signal channel connected to each transducer, wobble switch means on the output side of each of said wobble signal channels, said wobble switch means each having a set of normally closed contacts, a main relay for actuating said system, ball operated energizing means for said main relay, said normally closed contacts of said wobble switch means being connected in series with each other and said main relay; said main relay becoming energized in response to the actuation of ball operated energizing means when there are no wobbling pins in the course of play of said game and all of said wobble contacts remain closed, and said main relay becoming energized only after any one of said wobble switch means first becomes energized in response to the wobble of the respective pin and then de-energized upon termination of said wobble, whereby said machine has a variable starting delay resulting from the closing of said pit switch, said delay time being a function of the duration of a wobble of any pin in the course of said game.

References Cited in the le of this patent UNITED STATES PATENTS 2,338,733 Patterson et a1. Jan. 11, 1944 2,514,457 Schmidt July 11, 1950 2,520,662 Timberlake Aug. 29, 1950 2,559,274 Broekhuysen July 3, 1951 2,613,933 Johns et al. Oct. 14, 1952 2,697,605 Montooth et al Dec. 21, 1954- 

